Can I display the image from a camera on a plane in the same scene?
I don't think  Blender is capable of render two cameras in the same process.

But you can make the light from the sides reaching the camera in the old way: make a hole in the ship and bend the rays by 90° (with a mirror).



In the picture above you can see Suzanne in a whaleish vehicle with some other smaller spaceships (red, yellow and green) on both sides.



Anyway I think it would be easier to put two cameras and composite the holograms in post. You'll surely have much more control on their final appereance.